Thrombosis may lead to cardiac, cerebral and pulmonary circulation disorders such as acute myocardial infarction, apoplexy and pulmonary embolism etc., which threatens people's health and lives, and is also a common complication of surgical operations and a factor of reocclusion after interventional angioplasty. Although thrombolytic therapy, interventional therapy and even surgical treatment that were developed in recent years have made a remarkable progress in treating acute myocardial infarction and cerebral infarction, greatly improved the success rate of rescuing patients and significantly improved the quality of life, the disability rate of cardiac and cerebral vascular diseases is still up to 30%. Therefore, developing a new medicament for preventing and treating cardiac and cerebral vascular diseases becomes a focus of attention and study in recent years.
There are many factors resulting in thrombosis, for example, adhesion and aggregation of platelet on the surface of injured vascular wall, blood stasis, formation of thrombin caused by activation of clotting factor, low activity of plasmin etc. In these factors, platelet is the essential material for thrombosis; therefore, the inhibition of platelet aggregation plays an important role in the prevention and treatment of thrombosis. Adenosine diphosphate (ADP) is an important agonist for amplification of platelet activation and aggregation effect, and it has become an important approach to prevent pathological thrombosis (coronary heart disease, cerebrovascular disease, pulmonary embolism, thrombophlebitis etc.) and myocardial infarction, unstable angina pectoris, peripheral vascular disease, congestive heart failure and the like by blocking ADP receptor so as to inhibit the function of platelet.
Clopidogrel is a first-line clinical antiplatelet agent of ADP receptor inhibitor at present, which is developed based on structural modification of a conventional antiplatelet agent Ticlopidine. As soon as the product of Clopidogrel came into the market, it quickly occupied the market by virtue of its stronger antithrombotic effect and smaller ADR. However, during more than ten years of clinical practices, its side effects of TTP and hemolytic uremic syndrome (HUS) etc. have been discovered. It is noteworthy that Clopidogrel, while producing an antiplatelet pharmacological action, also exhibits side effect of bleeding tendency. Clopidogrel has a longer Tmax in therapeutic dose and slow onset, therefore, its administration dosage is hard to control, which would probably further increase the bleeding tendency. Meanwhile, as Clopidogrel is an oily substance with extremely weak alkalinity, it can be salified by reacting with a strong acid, and it is hard to purify. The salts of Clopidogrel are unstable under humid conditions, and its free base would be precipitated again, and due to its strong acidity, it is also limited to some extent in terms of formulation.
Then based on Clopidogrel, Daiichi Sankyo Company Limited of Japan and Eli Lilly and Company of USA co-developed a new antiplatelet agent Prasugrel, another ADP receptor inhibitor. Many researches have proved that Prasugrel is more active and have a faster onset of action than Clopidogrel, and the difference between patients' reactions to Prasugrel is smaller than to Clopidogrel. The results of clinical controlled experiment of Prasugrel with Clopidogrel indicated that Prasugrel is more effective in reducing mortality caused by non-fatal heart attacks and apoplexy, but leads to more bleeding in patients. Therefore, it is necessary to research and develop a new medicament with good safety and antiplatelet aggregation activity.

Synthetic methods and reviews concerning the thienopyridines compounds can be found in the following literatures: CN1683373, U.S. Pat. No. 4,681,888, U.S. Pat. No. 4,529,596, GB1501797, WO02059128, U.S. Pat. No. 4,174,448, GB1561504, WO2004094374, JP6135970 and JP63264588.